Heat dissipation device having an improved fin structure

ABSTRACT

A heat dissipation device for dissipating heat from an electronic element, includes a base plate for absorbing heat from the heat-generating component, a fin unit located above the base plate and having a plurality of fins stacked together, and at least a heat pipe having an evaporating section thermally engaging with the base plate and a pair of condensing sections extending through the fins. Each of the fins has a plurality of parallel and protruding flanges on a top face thereof. The protruding flanges of the fins are of equal height and parallel to short sides of the fins. Each protruding flange has a length equal to that of the short sides of the fins. A distance between two neighboring ones of the protruding flanges located between the condensing sections is the same. The protruding flanges are provided for increasing a heat dissipation area of the fin.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a heat sink, and more particularly to a heat sink having a plurality of fins to remove heat from an electronic heat-generating component, wherein the fins have an improved structure.

2. Description of Related Art

Heat sinks are usually used to remove heat from electronic heat-generating components, such as central processing units (CPUs) etc., to keep the components in stable operation. A typical heat sink comprises a base for contacting with the heat-generating component to absorb the heat of the heat-generating component and a plurality of parallel planar fins attached to the base by soldering or adhering. The fins are used for dissipating the heat to ambient air. For enhancing heat dissipation efficiency, a fan is usually mounted on a top or a side of the heat sink to impel air to flow between the fins.

To meet a requirement of heat removal from the heat-generating component which generates more and more heat, it is current way to enlarge the total outer area of the fins by increasing the number of the fins or enlarging a dimension of each fin. However, such thermal resolutions have their limitations. Because a space in a computer enclosure is crowded by various components and the space available for the heat sink cannot be readily increased, an increase of the size of the fins is not feasible. Furthermore, the larger number the fins have, the denser the fins are, and further the narrower the channels between the fins are. If the air channels are too narrow, the air cannot smoothly flow through the channels, which impedes the heat dissipation of the heat sink even if the number of the fins is increased.

What is needed is a heat sink in which has a great heat dissipating efficiency by means of improving heat exchange between the fins and air flowing through the heat sink under a condition that the size and number of the fins are not necessary to be increased.

SUMMARY OF THE INVENTION

The present invention relates to a heat dissipation device for dissipating heat from a heat-generating electronic element. The heat dissipation device includes a base plate adapted for absorbing heat from the heat-generating component, a fin unit located above the base plate and having a plurality of fins stacked together. Each of the fins has a plurality of parallel and protruding flanges on a top surface thereof. At least a heat pipe has an evaporating section thermally engaging in the base plate and a pair of condensing sections extending through the fins. The protruding flanges of the fins are of equal height and parallel to opposite short sides of the fins. A length of each of the protruding flanges is equal to that of the short sides of the fin. The protruding flanges increase heat dissipation area of the fin unit, thereby increasing heat dissipating effectiveness of the heat dissipation device.

Other advantages and novel features will become more apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiment. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.

FIG. 1 is an assembled view of a heat dissipation device in accordance with a preferred embodiment of the present invention;

FIG. 2 is an exploded, isometric view of FIG. 1;

FIG. 3 is a partially exploded view of a heat sink of the heat dissipation device in FIG. 2; and

FIG. 4 is a front elevational view of the heat dissipation device in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 and 2, a heat dissipation device in accordance with a preferred embodiment of the invention comprises a base plate 10, a fin unit 20 located above the base plate 10 and two heat pipes 30 connecting the fin unit 20 and the base plate 10 together.

The base plate 10 is a flat heat conducting plate, and comprises a bottom surface (not shown) for absorbing heat from a heat-generating component (not shown) and a top surface (not labeled). The base plate 10 defines two parallel receiving grooves 12 at the top surface thereof. The receiving grooves 12 are located at a central portion of the top surface of the base plate 10, parallel to two opposite sides of the base plate 10 and configured to receive corresponding portions of the heat pipes 30 therein.

Also referring to FIGS. 3 and 4, the fin unit 20 consists of a plurality of fins 22 which are stacked together. Each of the fins 22 is preferably formed by aluminum extrusion, Each of the fins 22 is a rectangular flake and defines two row of through holes 220 therein. Each row has two through holes 220. Furthermore, each fin 22 has a plurality of protruding flanges 222 projecting upwardly from a top surface thereof. The fins 22 are spaced from each other with a constant distance and parallel to the top surface of the base plate 10 and parallel to each other. The two rows of through holes 220 are spaced from each other and are respectively adjacent to and parallel to two opposite lateral sides of the fin 22. The through holes 220 are provided for receiving the heat pipes 30 therein. The protruding flanges 222 are parallel to the two opposite lateral sides of the fin 22 and spaced from each other with a predetermined distance, except two neighboring flanges 222 which are located adjacent to the through holes 220. Each of the flanges 222 is an elongated strip and perpendicular to the top surface of the fin 22. A distance between the two neighboring fins 22 adjacent to and separated by the through holes 220 is determined by a caliber of the heat pipe 30, which in this embodiment is bigger than that between other two neighboring flanges 222. The fin unit 20 defines a plurality of first air passages 26 between every two neighboring fins 22 and every two neighboring flanges 222 and defines a plurality of second air passages 28 between every two neighboring fins 22 and two neighboring flanges 222 adjacent to the through holes 220. The first air passages 26 is configured to facilitate airflow generated by a fan (not shown) mounted on a front sided of the fin unit 20 passing therethrough. The second passages 28 are configured to guide the airflow toward the heat pipes 30 to directly bring heat accumulated in the heat pipes 30 into ambient.

Each of the heat pipes 30 comprises an evaporating section 32 received in the corresponding receiving groove 12 of the base plate 10 and two condensing sections 34 extending perpendicularly and upwardly from two opposite ends of the evaporating section 32. The two condensing sections 34 are engagingly received in the through holes 220 of the fin unit 20 and perpendicular to the fins 22.

In an assembly of the heat dissipation device, the evaporating section 32 and the condensing sections 34 of the heat pipe 30 are respectively received in the receiving grooves 12 of the base plate 10 and the through holes 220 of the fin unit 20, and secured therein by any known means, such as soldering or adhering.

In use of the heat dissipation device, heat produced by the heat-generating component is absorbed the base plate 10 and then transferred to the fin unit 20 via the heat pipes 30 to dissipate into ambient. The fan (not shown) can be mounted at the front or rear side of the fin unit 20 to generate the forced airflow through the fin unit 20 via the first air passages 26 and the second air passages 28. The protruding flanges 222 protruding upwardly from the top surface of the fins 22 can increase a contact area between the airflow and the fins 22, thereby increasing heat exchange between the fins 22 and the airflow and further enhancing heat dissipation efficiency of the heat dissipation device.

It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention 

1. A heat dissipation device adapted for dissipating heat from a heat-generating electronic element, comprising: a base plate adapted for absorbing heat from the heat-generating component; a fin unit located above the base plate and having a plurality of fins stacked together, each of the fins having a plurality of parallel and protruding flanges for increasing a heat dissipation area of the each of the fins; and at least a heat pipe having an evaporating section thermally contacting with the base plate and a pair of condensing sections extending through the fins; wherein the protruding flanges of the fins are of equal height and parallel to short sides of the fins, a length of each of the protruding flanges is equal to that of the short sides of the fins, and the protruding flanges located between the condensing sections are spaced from each other with an equal distance.
 2. The heat dissipation device of claim 1, wherein the flanges located at two flanks of the condensing sections of the at least a heat pipe are spaced from each other with an equal distance.
 3. The heat dissipation device of claim 2, wherein the flanges are raised from a top surface of the each of the fins which is parallel to a top surface of the base plate.
 4. The heat dissipation device of claim 3, wherein each of the flanges is an elongated strip and perpendicular to the top surface of the each of the fins.
 5. The heat dissipation device of claim 2, wherein a plurality of air passages is defined between every two neighboring fins and every two neighboring flanges.
 6. The heat dissipation device of claim 1, wherein the condensing sections are perpendicular to the evaporating section, the top surface of the base plate and the fins.
 7. A heat dissipation device, comprising: a base plate adapted for absorbing heat from the heat-generating component; and a fin unit located over the base plate and having a plurality of fins horizontally stacked together; wherein each of the fins have a plurality of protruding flanges arranged on a surface thereof, the flanges divide a channel between every two neighboring fins into a plurality of parts, and each of the parts forms an elongated air passage.
 8. The heat dissipation device of claim 7, wherein the flanges are raised from a top surface of the each of the fins which is parallel to a top surface of the base plate.
 9. The heat dissipation device of claim 8, wherein each of the flanges is an elongated strip and perpendicular to the top surface of the each of the fins.
 10. The heat dissipation device of claim 7, further comprising at least a heat pipe thermally connecting the fin unit and the base plate together.
 11. The heat dissipation device of claim 10, wherein the at least a heat pipe has a evaporating section embedded in a top surface of the base plate and two condensing sections extending through the fins.
 12. The heat dissipation device of claim 11, wherein the two condensing sections are perpendicular to the evaporating section, the top surface of the base plate and the fins.
 13. A heat dissipation device for dissipating heat generated by an electronic component, comprising: a base plate adapted for connecting with the electronic component; a fin unit thermally connecting with the base plate, wherein the fin unit consists of the a plurality of aluminum-extruded fins stacked on each other, each of the fins has opposite faces and has a plurality of protruding flanges on at least one of the opposite faces, a plurality of air passages being defined between two neighbor fins and the plurality of protruding flanges.
 14. The heat dissipation device of claim 13 further comprising a heat pipe having an evaporating portion embedded in the base plate and a condensing portion extending through the fins of the fin unit.
 15. The heat dissipation device of claim 13, wherein each of the fins is rectangular in shape, and the protruding flanges are parallel to each other and to opposite short sides of the each of the fins.
 16. The heat dissipation device of claim 14, wherein each of the fins is rectangular in shape, and the protruding flanges are parallel to each other and to opposite short sides of the each of the fins.
 17. The heat dissipation device of claim 16, wherein the protruding flanges are spaced from each other with a same distance, except two neighboring ones of the protruding flanges adjacent to the condensing portion of the heat pipe. 